Chihuahuan desert on fans, terraces and weakly consolidated pediments

This large EU forms a nearly continuous band skirting the eastern and southern limits of the study area, running roughly from Redington south and west to Cienega Creek. The terrain is 60% gently rolling hills, 12% flat terraces, and 6% bottomlands, with the remainder slopes greater than 18%. A mix of creosote and whitethorn acacia typically dominate the vegetation, although either (but not both) may be absent from a site. Common associates include mariola (Parthenium incanum), sandpaper bush (Mortonia scabra), and soaptree yucca. Grasses are highly variable, and the southern aspects often hold less than 5% cover. Mesquite is usually limited to bottomlands, but these can be extensive, with 25-39% cover. The EU is largely on limy soils, but also includes 840 ha of a region between Colossal Cave and Cienega Creek, 2000 acres of non-limy soils that is primarily rolling hills of creosote and whitethorn, with mesquite in the draws. These non-limy pediments and fan are relatively disturbed, with a quarry on Cross Hill, and the tracks of the Union Pacific. We have no photos from these non-limy areas.

Photo Point 15, on a limy fan just north of Buehman Canyon, near Redington, 3300 feet, March 2008. Whitethorn is the clear dominant, with 10-14% cover. Soap-tree yucca and mariola are common associates, but creosote is uncommon. Sideoats grama, bush muhly, and tobosa grass gave another 5-9% cover. Note the contrast with the dark hill in the background, which is Sonoran desert — palo verde and saguaro.

Photo Point 13, about 2 miles SW of Redington, 3600 feet, March, 2008. Sotol and beargrass dominate the north-facing slope, along with the grass called slim tridens. The warmer slope, back left, is mostly creosote and ocotillo. Yucca is a common associate.

Photo Point 79, the view south from 1-10, about 1 mile west of Cienega Creek, 3600 feet, September, 2008. Whitethorn, creosote, and mariola co-dominate, each with 5-9% cover. Zinnia and sandpaper bush are common associates. Grasses are sparse. Empire Mountains in background.

Desired Conditions

Desired conditions are adapted from Desert, mid-scale desired condition statements in March 2010 Coronado National Forest planning documents.

Fires are rare. Native species are present with no signs of soil compaction or accelerated erosion. A mix of shrubs, succulents, and grass is evident.

Primary treatment options (estimated representative project size range):

• Prescribed fire and/or wildfire to maintain openings, reduce ground fuels, and site prep (1,000 to 30,000 acres per project)

Supplemental treatment options (estimated representative project size range):

• First-entry mechanical treatments to prepare for fire reintroduction: mastication/crushing, pushing, thinning (up to 2,500 acres per project) 
• Thinning around developments for safety-related fuel reduction (up to 500 acres per project)
• Cut and scatter brush along trails (up to 500 acres per project)
• Herbicide and mechanical treatment for exotics and shrub management to maintain openings (up to 1,000 acres per project) 
• Fuelwood sales (smaller diameter, including aspens) to reduce fuel loading (up to 300 acres per project)

Other considerations:

May be wilderness considerations with treatments.

Other vegetation classifications: